Transmitter Tutorial

Transmitter

Level 1 - Fundamental Training

Level 1 Fundamental Training

1

Level 1 - Transmitter

Contents Topics: • Types of Transmitter Outputs • Analog Transmitter • Smart Transmitter • Fieldbus Transmitter Similarity between FF & PA Difference between FF & PA Benefits of FF against PA • Exercise

2

Slide No: 3-4 5-7 8 - 22 23 - 72

73 - 75

FF = Foundation Fieldbus PA = Profibus Level 1 - Transmitter

Power Point Presentation Handouts

Transmitter


Transmitter Overview Standard current or voltage signal (ANALOG)

3

Standard current or voltage & digital signals (SMART) Only high speed digital signals (FIELDBUS) Output Signal

Analog/Smart/Fieldbus Electronics

Transmitter

Input Signal

(To translate useable electrical signal to standard electrical signal)

Sensing element + Electrical Circuitry

Transducer

Process Pressure

(To convert mechanical to useable electrical signal) Level 1 - Transmitter

Types of Transmitter Outputs

4

Analog Transmitters – Pure Analog Signal – 4-20 mA or 1-5V or 3-15 psi pneumatic signal Smart Transmitters – Digital communication (diagnostic signal) superimposed on analog signal (4-20 mA or 1-5V) Profibus Transmitters – High Speed Digital signal only Foundation Fieldbus Transmitters – High Speed Digital signal only – Control in the Field functionality



Transmitter


Analog Transmitter Overview

5

• Analog transmitter is made up of two basic component:

» Sensor Module » Analog Electronics • Signal from sensor module is amplified & translated into standard current or voltage signal by the electronics Pressure Input Signal

Pressure Transducer Sensor Signal Conditioning Capacitance /

Zero Standard Output Signal

mV Signal

Span

Eg).

Output = 4-20 mA current signal only Level 1 - Transmitter

How Analog Transmitters Works ?

6

Sensor registers process variable. Sensor board outputs a corresponding electrical signal to output electronics. Signal conditioned & translated to a standard current signal Zero & Span Pots are used to set operating range.

Sensor Circuit Board

uF

Signal Conditioning

set 20 mA value Span Pot

Sensor Block PV

Zero Pot set 4 mA 4-20 mA Amplified value Current Only Signal Output

Cable Link

Transducer

Output Electronics

Loop wire pair (Power Cable) Level 1 - Transmitter


Transmitter


4-20 mA Current Loop

7

The voltage or current in the wire pair represents one process variable. Field Indicator Current Loop Power Supply

Analog Transmitter

4 to 20 mA 250 Ω

250 Ω

1-5V

1-5V

4 - 20 mA

To DCS, Recorders Control Loop To Control Room Device


Smart Transmitter

8

• Smart transmitter is an intelligent device made up of modems, microprocessor and memory which allow : » Remote Communication » Diagnostics self-test functions Pressure Input Signal Transducer

EEPROM

Pressure Sensor

Capacitance / mV Signal

Data A/D

Resistance Module Temperature Sensor

Eg).

µ

D/A

Communications Standard Output Signal

Output = 4-20 mA current & Digital HART Signal Level 1 - Transmitter


Transmitter


How Smart Transmitter Works ? STORES: •Correction Coefficient • Module Information

Sensor Module PV

Sensor Block

Cable Link

9

Electronics + Memory

mV/uF

A/D

Digital; PV + Term. Temp Values

μ

4-20 mA & digital communication signal

Digital; corrected PV Value D/A Communication

Temperature Sensor

Bell 202 Physical Layer

Memory

Measures ambient/Terminal temp.

Smart Electronics STORES: • Sensor Performance Curve • Range Values • Transmitter Configuration

Loop wire pair (Power Cable)


Analog vs Smart Transmitter

10

Real Time vs Sampling Pressure Input 4–20 mA Output Sampling 4–20 mA Output

A/D Conversion

• Analog output follow sensor Analog output instantaneously. Transmitter • Analog output will be a continuous curve. • Magnitude of sensor output Smart is sampled multiple times per Transmitter second to give discrete values.

D/A Conversion

• Analog output will undergo small step change with respect to sensor output. Level 1 - Transmitter


Transmitter


®

HART Protocol

11

Highway Addressable Remote Transducer • An open protocol » Users are not locked into a single supplier +0.5 mA

Freq. Shift Binary Status

1200 Hz

“1”

2200 Hz

“0”

0 mA –0.5 mA

1200 Hz 2200Hz HART protocol uses a frequency shift keying based on Bell 202 physical layer to superimpose digital communication on to the 4 - 20 mA current loop.

20 mA

Average modulating current signal is “ZERO”

Analog Output representing process variable

Digital Communications (HART Protocol) Therefore HART protocol does NOT affect 4-20 mA signal 4 mA Level 1 - Transmitter

4-20 mA Current Loop

12

The voltage or current in the wire pair represents one Modulating Current process variable. Field Indicator

Current Loop Power Supply

Smart Transmitter

4 to 20 mA 250 Ω

250 Ω

1-5V

1-5V

To DCS, Recorders

Communication Signal

4 - 20 mA

Control Loop To Control Room Device



Transmitter


HART Communications E=IR ±0.5 mA * 250Ω = ±0.125 V

13

Modulating Voltage Communication Signal Physical layer = BELL 202 FSK Transmission Rate = 1.2kbit/s

To Establish Communication with HART Communicator

Modulating Current Communication Signal S

Z

COMM

Minimum 250 Ohms !

4 - 20 mA

-

+

TEST

FIELD TERMINALS

Average HART voltage signal = ±0.3 V

Power Supply

Communication signal riding on 44-20 mA Analog signal

But HART Circuit recognize at least ±0.125 V as a valid signal Level 1 - Transmitter

Remote Communication with HART protocol

14

Control System

150Ω

100Ω

Fuse Box

Chart Recorder

Power Supply Marshaling Panel

HART Junction Box communicator can be connected to any points in the loop having at least 250 Ω

9

Where to establish communication with the Smart Transmitter? Level 1 - Transmitter


Transmitter


HART Communicator for Smart Transmitter

15

Communicator MUST hold the Device Descriptor files for that particular Device Model to establish communication. • Download DDs » Device Version. » Software Rev.

Communicator Module Memory

• Field Upgrade-able » Latest device versions & software revisions can be added-on for advanced functions.

SMART Transmitter Memory

275 Memory

Working memory Holds the connected transmitter’s configuration

Stores configurations for future use & DDs

Configuration data stored in the electronics

Data Pack Optional, holds transmitter configurations for future use Level 1 - Transmitter

Multidropping is possible with Digital Transmitters

16

Maximum 15 HART devices can be multi-dropped. Only Digital Communication Signals Power Supply

4-20 mA + Digital Comm. Signal 4 mA 250Ω

1

2

ica te

Co m

Co mm un

Assigned Polling Address via Communicator

Stand-alone Address = 0

m u 3 nica - - - - - - - - - - - - 15 te

Poll Poll 2 15 Address Address Level 1 - Transmitter


Transmitter


Smart Transmitter performs continuous diagnostics

17

Process Variable Out of Range 3.9 Analog Output (mA)

4

20

20.8

Normal Operating Range

3.75

22 LOW

HIGH

Hardware Alarm

Diagnostic Information: – Process Alarm •Pressure drop below 4 mA point ⇒ Output current fixed at 3.9 mA • Pressure rise above 20 mA point ⇒ Output current fixed at 20.8 mA • Alarm message displayed

– Hardware Failure Alarm •HIGH or LOW ⇒ User selectable by a jumper switch on the electronics • During failure ⇒ Output current fixed at either HIGH or LOW value Level 1 - Transmitter

Advantages of Smart Transmitter

18

• Process Variable Reading

0

Can read the Process Variable when the 4–20 mA points are exceeded 200 140 80

PV = 40 psi AO = 3.9 mA

4 mA

20 mA PV = 160 psi AO = 20.8 mA

• Multiple Digital Outputs » Primary = Digital representation of Process Pressure » Secondary = Temperature inside Sensor Module » 3rd = Not used on this Model » 4th = Not used on this Model Level 1 - Transmitter


Transmitter


Benefits of Smart Transmitter Against Analog Transmitter

19

The digital format of the smart transmitter makes the following characteristics possible: • Higher accuracy • More Features • Wider Rangeability • Simplified Maintenance • Easier Commissioning • Multiple Sensor Readout • Better Electronic Stability


FF PA

Fieldbus Application • Can be used for control applications: pressure, temperature, level & flow • Supports Intrinsic Safety (I.S.) with bus powered devices

Safe area PS PC

20

Control System

T SB 1 2

Hazardous Area

k T



Transmitter


FF PA

Fieldbus Network Standard

21

• IEC 1158-2 Standard Operator Interface Junction Boxes

Power Supply 9~32 V

Couplers

H1 Segment 1 Terminator

Terminator

Power Filter

Local Operator Interface

Configurator Power Filter


FF PA

Fieldbus Supports Multiple Topology

22

• Topology describes the Shape of the Network Control Highway Fieldbus I/O

Point to Point

Branch

Junction Box

Daisy Chain

Tree Level 1 - Transmitter


Transmitter


FoundationTM Fieldbus Communication Protocol

FF PA

23

Protocol FoundationTM Fieldbus protocol is the same on both Highway 1 and 2 Physical Layer Highway 2 for Local and Wide Area Network communications. (100 Mbits/sec or 1 Gbits/sec) Industry Standard Ethernet Highway 1 for Process Automation

(31.25Kbits/sec) Uses existing cabling Power & Signal Intrinsic Safe Field Devices


FoundationTM Fieldbus Topology

FF PA

24

Speed 100 Mbits/s High Speed Ethernet Highway 2 Highway 1 to 2 Bridge

Speed 31.25 Kbits/s Highway 1

Control Valves

On/Off Actuators

Tx’s

Motor Starters

Temp Tx



Transmitter


Profibus Communication Protocol and Physical Layer Family

FF PA

25

Profibus FMS for Local Area Network communications.

(Up to 12Mbits/sec @ 100 metres) Signal (RS485) CNC Devices Computer to Computer Profibus DP for Devices

(Up to 1.2Mbits/sec @ 200 metres) Signal (RS-485) Distributed Input/Output Systems Non Intrinsic Safe Field Devices Profibus PA for Process Automation (31.25Kbits/sec) Uses existing cabling Power & Signal Intrinsic Safe Field Devices Level 1 - Transmitter

FF PA

Profibus Topology

26

Up to 12Mbits/s @ 100 metres

FMS PLC

DP

Up to 1.2Mbits/sec @ 200 metres

31.25 or 62 Kbits/s

DP Power Supply

DP to PA Converter On/Off Actuators

31.25 Kbits/s

PA

Motor Starters

Single point of Failure

Control Valves

Tx’s Level 1 - Transmitter


Transmitter


FF PA

What is Fieldbus?

27

• Fieldbus is a network • Devices sit in parallel between the wires • Transmission Rate = 31.25 kbit/s

Fieldbus Segment Only Digital Communication Signals

Terminator

Terminator Power Conditioner

Monitor or Control

Fieldbus Power Supply

Field Devices Level 1 - Transmitter

H1 - 31.25 kbit/s Field Devices

FF PA

28

• Can be powered directly from the fieldbus segment • Can operate on wiring previously used for 4-20 mA devices H1 Fieldbus Segment (wire-pair) Power Supply

Power Conditioner

T

Field Devices powered from fieldbus

T

Standard (4-20 mA) Wire-pair

Power & communication on the same pair of wires. Level 1 - Transmitter


Transmitter


FF PA

H1 Signal Transmission Wave shape at sending device

29

Wave shape on fieldbus

I (Current)

V (Voltage) 0.75 - 1 V pp 16 - 20 mA pp

Variable 0

Power 9 to 32 V

0

Time

Time

Equivalent Circuit Diagram

Power = Max. 32 V

100Ω

100Ω

1μF

1μF

Terminator

Terminator Device Level 1 - Transmitter

FF PA

Terminators

30

• R-C circuit • impedance matching module • to prevent distortion & signal loss due to reflection at the ends of fieldbus cable • for voltage mode signal on the segment Trunk Terminator

Power Supply

Terminator

Power Conditioner 100 Ohms 1uF Spur Ground



Transmitter


FF PA

Power Conditioning

31

Ordinary power supply will absorb signal on the cable – trying to maintain constant voltage level on the cable Therefore, has to be conditioned for fieldbus – by putting an inductor between power supply & fieldbus wiring Active filter, equivalent to:

Power Supply For Multiple Segments

100 Ohms 10 mH

Power Conditioner

Fieldbus

All ground terminals should be connected to Instrument Ground Bar or Earth Ground

Ground


FF PA

Segment Power

32

• The voltage supplied to the fieldbus cable can be as high as 32 V. • The voltage at any device can be as low as 9 V for the device to operate correctly.

Power Supply

VPS

Power Conditioner VPC

V1

T

Iq1

V2 Iq2

Iq3

Vn

V3

T

Iqn

VPS - VPC < 32 v Vn

> 9v Level 1 - Transmitter


Transmitter


Common Physical Layer

FF PA

33

Wiring Savings are the same

Before

After


Common Physical Layer

FF PA

34



Transmitter


FF PA

Common Network Components

35

Terminator

Cap

Brick

Gland Level 1 - Transmitter

FOUNDATION™ Fieldbus Architecture

FF PA

36

• 3 main components

Field Device 1

User Layer

Communication “Stack”

Physical Layer

Key F.F Technology Differentiator Interface for user interaction through “Blocks”

“Protocol Stacks” handles Communications Device connection to network

Field Device 2

User Layer


Physical Layer

Fieldbus Network Level 1 - Transmitter


Transmitter


FF PA

Physical Layer

37

• Composed of physical medium (eg. wire-pair) • Receives massage from the communication stack & converts the message into physical signals on the fieldbus wire to a digital representation that a micro-processor can understand • Manchester Encoding Technique • 31.25 Kbaud Physical Layer FOUNDATION™ fieldbus H1 Segment Level 1 - Transmitter

FF PA

Physical Layer

38

• Fieldbus signals are encoded using Manchester Encoding Data is combined with clock signal to create “synchronous serial” signal.

Fieldbus Messages

CLOCK 1 Bit Time

Voltage

DATA

Time

1 0

+ ENCODING

0

1

1

0

0

-



Transmitter


FF PA

Communications Stack

39

• Device communication software provides encoding & decoding of user layer messages provides deterministic control of message transmission provide message transfer Communication • Data Link Layer (DLL) “Stack” Controls transmission of messages onto the fieldbus through the Link Active Scheduler (LAS) Physical Layer Provides various possibilities for application layer to send data to FOUNDATION™ fieldbus H1 Segment other stations Level 1 - Transmitter

FF PA

Communications Stack

40

• Link Active Scheduler (LAS) Only one LAS per Fieldbus Segment If the LAS fail, a Backup LAS (LM) will become active Traffic police for segment 1 Controller LAS

Traffic police for segment 2

Bridge LAS

BD

BD

BD

LM

BD

LM

LM

LM

Link 1 or Segment 1

Link 2 or Segment 2



Transmitter


FF PA

User Layer • Provides the interface for user interaction with the system Blocks - resource, transducer, and function • Supports DDs to allow host system to know device capabilities • Key FF technology differentiator

41

User Layer


Physical Layer FOUNDATION™ fieldbus H1 Segment Level 1 - Transmitter

User Layer - Resource Block

FF PA

42

Describes characteristics of device – Dev Type – Dev Rev – Mode – Master Reset Monitors over-all device status Only one resource block in each device



Transmitter


FF PA

User Layer - Transducer Block

43

Interface device hardware to function block Input transducer block – processing of sensor signal such as characterization & trimming Output transducer block – processing of actuator & feedback signal Factory & User Characterization

Sensor

Unit

Trim

Channel Pressure

Temperature


FF PA

User Layer - Function Block

44

Performs the basic time-critical functions: – measurement – control & control-selection – calculation & signal selection – alarm – actuation & etc. Configurations are built using function blocks



Transmitter


FF PA

User Layer - Function Block

45

Function blocks can be linked together

– within a device and/or to other devices Function blocks can be distributed to the devices

– download via the Host Control is distributed “on the wire” OUT

IN

OUT

AI-110

PID-110

BCKCAL_IN

TAG: LT108

TAG: DVC108

H1 CAS_IN

PID-110

AI-110

LT

AO-110

BCKCAL_OUT

AO-110

TAG: DVC108

DVC Level 1 - Transmitter

FF PA

Control Anywhere

46

• FOUNDATION™ Fieldbus devices have the capability to support field-based control TODAY • Regulatory control without the cost of a DCS or Controller! Host

Valve Transmitter BKCAL_IN OUT

AI

IN

OUT

PID

BKCAL_OUT

FIELDVUE

CAS_IN

AO



Transmitter


FF PA

Device Descriptor (DDs)

47

• a “driver” for the fieldbus device New devices are added to the fieldbus by simply connecting the device to the fieldbus segment and providing the control system or host with the DDs. • to achieve interoperability allows operation of devices from different suppliers on the same fieldbus network with only one version of the host human interface


FF PA

Device Descriptor (DDs)

48

• contains standard device descriptions from the fieldbus foundation. – Universal parameters – Function block parameters – Transducer block parameters

incremental device descriptions from the suppliers – Manufacturer specific parameters Standard DDs

Incremental DDs

...

To Host System



Transmitter


FF PA

Automatic Address Assignment

49

A number of devices may be connected to the

bus at the same time. A configuration utility in the host then automatically assigns an unused address to each device. The user does not need to understand how to assign hardware addresses. “Plug and Play” Transmitters This enables fast and safe commissioning of the

Fieldbus Network No dip switches or software pre-configuration required Level 1 - Transmitter

FF PA

Polarity Insensitive Devices

50

Fisher-Rosemount Provide Polarity Insensitive

Foundation Fieldbus Devices This enables fast and safe commissioning of the

Fieldbus Network Rack Room Marshalling Panel

Wiring crossover is NO PROBLEM!

+

Field Junction Boxes

Host Termination Panel

+

Home Run Cable Junction Boxes



Transmitter


FF PA

On-Line Expansion

51

Devices may be connected to the bus On-Line

and used in Control Strategies without shutting down the Control System This maximises device flexibility, availability and ultimately process through put. Why Stop the process when you want to add a Field

Device ?


FF PA

Tag Search

52

Foundation Fieldbus provides a service for

finding devices or Function Blocks by TAG. Variables can also be found searching: TAG.Desired Parameter Can you remember the Transmitters Hardware

Address that you are looking for ? Extremely useful feature during plant start-up and operation.

FT102A or CTL01C03A01 Level 1 - Transmitter


Transmitter


FF PA

Unique ID

53

Foundation Fieldbus provides a UNIQUE ID

(Serial Number) in each Device. This Enables Device traceability from initial device manufacture. The UNIQUE ID contains the Device Manufacturer, Model Number, Location, Time and Date the devices operating system was downloaded . Useful for life Cycle Management and Material

Management Provides Device Traceability


FF PA

Trend Collection In Fieldbus Devices

Last 16 (Values + Status) + Timestamp of Last Value Collected

Trend Collection

Transd. Block

54

AI

PID

AO



Transmitter


FF PA

Common sense of time

55

All devices in the network share a common sense

of time, which allows precise scheduling of activities. The Application Clock Time Distribution function synchronises all Fieldbus devices. The devices maintain their application clocks between synchronisation messages. The application time enables the devices to time

stamp data (variables, alarms etc.) at source. Scheduling between devices provides tighter control.


FF PA

A Typical Plant Today

56

Control in the Control System

DCS

Proprietary Bus

AI AI

PID PID

AO AO Profibus DP

4 - 20 mA

DP/PA Coupler

Profibus PA



Transmitter


FF PA

A Typical Plant Today

DCS

57

Foundation Fieldbus

PID PID

PID PID

AI AI

AI AI

AO AO


Standard Function Blocks

FF PA

58

• Basic

Discrete Input Discrete Output Analogue input Analogue Output PID, PI, I Control P, PD Control Control Selector Manual Loader Bias/Gain Station Ratio Station



Transmitter


FF PA

Standard Function Blocks

59

• Advanced

Pulse Input Complex Analogue Output Complex Discrete Output Step Output PID Device Control Setpoint Ramp Generator Splitter Input Selector Signal Characteriser Lead Lag

Dead time Arithmetic Calculate Integrator(Totaliser) Timer Analogue Alarm Discrete Alarm Analogue Human Interface Discrete Human Interface


Online Control Strategy Modification

FF PA

60



Transmitter


FF PA

Online Control Strategy Modification

61


FF PA

A PLC Based System

62

• Information Mapping in a PLC Based System

DCS

Proprietary Bus Data Base Locations 4 - 20 mA

Profibus DP DP/PA Link Device

Profibus PA



Transmitter


A

FoundationTM

FF PA

Fieldbus Host

63

Information location with FoundationTM Fieldbus

DCS

Foundation Fieldbus

Data Base Location Level 1 - Transmitter

FF PA

Device Description Coverage

Supplier A pH Sensor Diag Functionality A

Interoperability via specifications

Sensor Diag Material Maintenance Log Auto Calb

64

Supplier B

Functionality B

Process Temp

TAG Descriptor Status PV1 -- DP PV2 -- Ambient Temp

Functionality C Pressure Flow Comp Material

Supplier C



Transmitter


FF PA

Device Description Coverage

65

Supplier B Supplier A

Functionality B Functionality A Interoperability via DDL and Function Blocks

Functionality C

Supplier C


FF PA

Future Proof the Investment

66

Full Device Description (DD) support enables you

to upgrade a FoundationTM Fieldbus Device by download the new DD’s to it.



Transmitter


FF PA

Future Proof the Investment

67

To upgrade a Profibus PA Device

– First find out which PA Communication Profile it is using. Version 1.0, 2.0, 2.1, 2.2 or 3.0. – Then find out if the hardware of your device can support the new PA Communication Profile. – Check the host PA Communication Profile. – Then return the device to the factory for the device to be upgraded. This upgrade can be performed on site if you have the correct revision of the device flashing tool and trained maintenance staff. Profibus PA = High Cost of ownership


FF PA

Device Status

68

All connectable variables have STATUS. STATUS reflects the measurement health and

Predictive Device failure analysis. Value: 234.5 m3/h Status: Good, Bad Sub-Status: Description of Fault Limit : High, Low, Constant or not limited Predictive Analysis : Impulse Line Plugging AI AI



Transmitter


FF PA

Predictive Device Failure Analysis

69

With Advanced Diagnostic Functionality we can

predictively detect device failures. This can be applied to the primary sensing element, the transmitter and/or the final actuator.

Blockage


Exercise

70

1. Define Foundation fieldbus. 2. State 2 distinguish difference between Foundation fieldbus and HART protocol. 3. State 2 similarities between Foundation fieldbus and HART protocol. 4. Name the three main layers of the Foundation Fieldbus Architecture. 5. Which one of the above layer is the key differentiator of Foundation Fieldbus Technology?



Transmitter


Exercise

71

6. Name the device in a fieldbus segment that acts as a “traffic police” to control the transmission of messages. 7. Name the block via where calibration is performed on the Foundation fieldbus device? 8. Name the block via where measurement configurations are made on the Foundation fieldbus device? 9. What is the allowable/required voltage range at any device in a fieldbus segment for the device to operate correctly. 10.Name the 2 special components that are required in a fieldbus segment to reduce signal distortion. Level 1 - Transmitter

Exercise

72

Rosemount measurement transmitters falls into the following categories: A. Analog B. Smart C. Foundation Fieldbus D. Profibus PA Select the category that best suits the following statements: 11. 12. 13. 14. 15. 16. 17. 18.

Outputs only 4-20 mA current. Enable control in the field. Outputs only digital signal related PV. Communication signal superimposed onto the 4-20 mA current signal. Uses BELL 202 physical layer for communication. Has built in function blocks such as AI, and PID. Made up of A/D modem, Micro-processor & D/A modem. Uses LAS to synchronize communication.

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Transmitter Tutorial

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